Water-cooled stoker



Nov. 28, 1939. J. 5. BENNETT WATER-COOLED STOKER Filed Nov. 4, 1937 2She ets-Sheet l JMW J Nov.'28, 1939. J, s, BEQNETT 2.1s1,473

WATER-COOLEID STOKER Filed Nov. 4, 19 37 2 Sheets-Sheet 2 I T l u IPatented Nov. 28, 1939 UNITED STATES 2,181,473 wArER-oooLEn STOKERJoseph S. Bennett, Merion, Pa.,

ican Engineering Company,

assignor to Amer- Philadelphia, I a.,

a corporation of Pennsylvania. Application November 4, 1937, Serial No.172,711

1 Olaim.

This invention relates to furnace stokers, and more particularly tofurnace stokers of the fluid cooled type.

In stokers of this type certain of the fluid conducting tubes of thecooling system associated therewith are protected, at least in part,from the heat of the furnace. Circulation of the fluid through suchtubes therefore often becomes sluggish, causing overheating of thetubes, and ultimately, damage thereto.

One object of the present invention is to provide an improvedcirculatory system for the fluid cooled section of furnace stokers ofthe stated character which will eliminate the abovementioneddifficulties. I

Another object is to so arrange the riser connections for the fluidcooled section of stokers that they will be exposed directly to the heatof the furnace, thereby inducing rapid circulation in the system. v

A further object is to arrange the riser connections of the fluid cooledsystem of the stoker in such a manner that they will serve the dualfunction of inducing rapid circulation in the system, and of cooling aportion of the walls of the furnace.

Other and further objects will become apparent as the description of theinvention progresses.

Of the drawings:

Fig. 1 is a longitudinal sectional view taken through a stoker furnaceshowing a construction wherein the tubes forming the cooling medium forthe tuyres, and the riser connections for the cooling section of theretorts, extend upwardly and form a portion of the front wall of thefurnace.

Fig. 2 is an enlarged detail sectional View of the upper header shown inFig. 1, and

Fig. 3 is an elevational view with a portion of the header broken away,taken substantially along line 33 of Fig. 2.

The drawings illustrate a construction wherein the boiler 56 of'thefurnace 51 is fired by a stoker 58 of the dump type. Boiler 56 comprisessteam drums 59 and connected by tubes 6|, and a mud drum 62 which isconnected to the steam drums by the usual banks of tubes 63. The innerbank of tubes 64 may be block covered at the lower end thereof, as shownat 65, and constitutes the bridge wall of the furnace. Stoker 5B is ofthe inclined grate underfeed type consisting of alternately disposedretorts 66 and tuyere rows 61. Each retort 66 has provided at the bottomthereof a series of feeding pushers 68, the lowermost of which restsupon a fuel supporting or dead plate 69. Mounted on a shaft 10,extending transversely at the lower, rearwardly disposed end of thestoker, are a series of dump plates ll. These plates are arranged inspaced relation with the lower ends of the boiler tubes 64 forming apas- 5 sage l2 therebetween through which the refuse fed from the stokermay pass. Adjustable means for shaft '10 may be provided to vary thesize of the discharge passage 12 if so desired.

Each tuyre row 61 of this construction has. 10 also provided in coolingrelation therewith one or. more tubes 13. These tubes are bent upwardly,as shown at 14, so as to extend along the inner surface of the frontwall 15 of the furnace, and terminate in a header [6. The lower ends oftubes 15 13 extend beyond the tuyere rows 61 and are bent downwardly, asshown at 11, and terminate in a header |8 disposed beneath dump platesII. The dead plates 69 have also mounted in cooling relation therewithone or more tubes 19. The for- 2 wardly disposed ends oftubes 19 areconnected to a header 80 mounted in any suitable manner beneath thestoker, while the rearwardly disposed ends thereof are bent downwardlyin parallel relation with the extended portions of tubes 13 and 25 alsoterminate at their lower ends in header 18. Header 86 is. connected toheader I6 by risers 8|. These risers extend upwardly along wall 15 andmay be disposed between the portions of the tubes 13 extending upwardlyfrom the tuyre rows. 30 Header I8 is connected to the mud drum 62 of theboiler bydowntake connections 82, while header 16 is connected to steamdrum 66 by tubes 83, the latter of which extending along the innersurface of the upper wall 84 of the furnace.

As shown more particularly in Figs. 2 and 3, the upper ends of risers 8|are connected to the corresponding tubes 83 by elbow connections 85. Theenlarged end 86 of each elbow 85 telescopes over the upper end of itscorresponding riser 8| and may be secured in position by any suitablemeans, such as by welding. The reduced end 81 of each elbow on the otherhand simply abuts the inner end of a corresponding tube 83. By thisconstruction proper circulation between the fluid 45 cooled. section ofthe stoker and the boiler is assured. I

It will be observed that the risers 8|, the upper portions of the tubes13, as well as the tubes 83, are directly exposed to the heat of thefurnace, 50 and consequently relatively rapid circulation will beinduced in the system.

While the embodiment herein shown and described is admirably adapted tofulfill the objects primarily stated, it is to be understood that the 55invention is not to be limited thereto, since it may be embodied inother forms, all coming within the scope of the claim which follows.

What is claimed is:

In a furnace, the combination of a boiler, a StOkBI for firing saidboiler, said stoker comprising alternately disposed retorts and tuyererows, fuel supporting means provided at the bottom of each of saidretorts and extending between adjacent tuyere rows, front, side and topwalls for said furnace, a pair of fluid conducting tubes mounted incooling relation with each of said tuyere rows, extensions for saidtubes extending vertically along said front wall, a header mountedinteriorly of said furnace connected to the upper ends of saidextensions, a series of tubes extending along said top wall connectingsaid header to said boiler, one or more fluid conducting tubes mountedin cooling relation with each of said fuel supporting means, a secondheader connected to the lower ends of all of said tubes, meansconnecting said second header to said boiler, a third header connectedto the upper ends of the tubes mounted in cooling relation with each ofsaid fuel supporting means, risers connecting said third and firstheaders, said risers extending vertically along said front wall betweenpairs of said first mentioned tubes, and a plurality of connecting meansmounted within said vfirst mentioned header and establishingcommunication between

